Chemical Ecology

the 'Faro Workshop'. Preface

by Adelino Canario

Canário, Adelino V.M.; Scott, Alexander P.; Hubbard, Peter C.; Barata, Eduardo N. Behaviour 145 (3), 1263-1265

Functional asymmetry in the olfactory system of a flatfish, the Senegalese sole (Solea senegalensis)

by Adelino Canario

Individual Variation In Alkaloid Content of Poison Frogs of Madagascar (Mantella; Mantellidae)

by Valerie Clark

Convergent Evolution of Chemical Defense In Poison Frogs and Arthropod Prey Between Madagascar and the Neotropics

by Valerie Clark

Clark et al_JNP2012_sugar-bile frog secretion

by Valerie Clark

Cooperation, Conflict, and the Evolution of Queen Pheromones

by Sarah Kocher

Semiochemical compounds of preen secretion reflect genetic make-up in a seabird species

by Sarah Leclaire

Several vertebrates choose their mate according to genetic heterozygosity and relatedness, and use odour cues to... more Several vertebrates choose their mate according to genetic heterozygosity and relatedness, and use odour cues to assess their conspecifics’ genetic make-up. In birds, although several species (including the blacklegged kittiwake) exhibit non-random mating according to genetic traits, the cues used to assess genetic characteristics remain unknown. The importance of olfaction in birds’ social behaviour is gaining attention among researchers, and it has been suggested that, as in other vertebrates, bird body scent may convey information about genetic traits. Here, we combined gas chromatography data and genetic analyses at microsatellite loci to test whether semiochemical messages in preen secretion of kittiwakes carried information about genetic heterozygosity and relatedness. Semiochemical profile was correlated with heterozygosity in males and females, while semiochemical distance was correlated with genetic distance only in male–male dyads. Our study is the first to demonstrate a link between odour and genetics in birds, which sets the stage for the existence of sophisticated odour-based mechanisms of mate choice also in birds.

Queen signal should be honest to be involved in maintenance of eusociality – chemical correlates of fertility in Ropalidia marginata

by Aniruddha Mitra

Insectes Sociaux online first 2011

Queens of many social insect species are known to maintain reproductive monopoly by pheromonal signalling of... more Queens of many social insect species are known to maintain reproductive monopoly by pheromonal signalling of fecundity. Queens of the primitively eusocial wasp Ropalidia marginata appear to do so using secretions from their Dufour’s glands, whose hydrocarbon composition is correlated with fertility. Solitary nest foundresses of R. marginata are without nestmates; hence expressing a queen signal can be redundant, since there is no one to receive the signal. But if queen pheromone is an honest signal inextricably linked with fertility, it should correlate with fertility and be expressed irrespective of the presence or absence of receivers of the signal, by virtue of being a byproduct of the state of fertility. Hence we compared the Dufour’s gland hydrocarbons and ovaries of solitary foundresses with queens and workers of post-emergence nests. Our results suggest that queen pheromone composition in R. marginata is a byproduct of fertility and hence can honestly signal fertility. This provides important new evidence for the honest signalling hypothesis.

Can Dufour’s gland compounds honestly signal fertility in the primitively eusocial wasp Ropalidia marginata?

by Aniruddha Mitra

Naturwissenschaften 2011

Unlike queens of typical primitively eusocial species, Ropalidia marginata queens are docile and non-interactive, and... more Unlike queens of typical primitively eusocial species, Ropalidia marginata queens are docile and non-interactive, and hence cannot be using dominance to maintain their status. It appears that the queen maintains reproductive monopoly through a pheromone, of which the Dufour’s gland is at least one source. Here we reconfirm earlier results showing that queens and workers can be correctly classified on a discriminant function using the compositions of their respective Dufour’s glands, and also demonstrate consistent queen-worker differences based on categories of compounds and on single compounds also in some cases. Since the queen pheromone is expected to be an honest signal of the fecundity of a queen, we investigate the correlation of Dufour’s gland compounds with ovarian activation of queens. Our study shows that Dufour’s gland compounds in R. marginata correlate with the state of ovarian activation of queens, suggesting that such compounds may portray the fecundity of a queen, and may indeed function as honest signals of fertility.

Regulation of reproduction in the primitively eusocial wasp Ropalidia marginata: on the trail of the queen pheromone

by Aniruddha Mitra

Journal of Chemical Ecology 2010

As expected for a primitively eusocial wasp, queens and workers are not morphologically differentiated in Ropalidia... more As expected for a primitively eusocial wasp, queens and workers are not morphologically differentiated in Ropalidia marginata. As unexpected for a primitively eusocial wasp however, R. marginata queens are remarkably meek and docile. Upon removal of the queen, one of the workers becomes extremely aggressive but immediately drops her aggression if the queen is returned. If the queen is not returned, this hyper-aggressive individual will develop her ovaries, lose almost all her aggression, and become the next queen of the colony. Hence we call her the potential queen (PQ). Because of the non-aggressive nature of the queen and because the PQ loses her aggression by the time she starts laying eggs, we consider the hypothesis that regulation of worker reproduction in R. marginata is mediated by pheromones rather than by physical aggression. Using the immediate loss of aggression by the PQ upon return of the queen, we develop a bioassay to demonstrate that the queen’s Dufour’s gland is at least one of the sources of the queen pheromone. Extracts of the queen’s Dufour’s gland (but not that of the worker’s Dufour’s gland) mimic the queen in making the PQ drop her aggression. We are also able to correctly classify queens and workers by a discriminant function analysis based on the chemical compositions of their respective Dufour’s glands.

The effects of seasonal climate changes in the Caatinga on tannin levels in Myracrodruon urundeuva (Engl.) Fr. All. and Anadenanthera colubrina (Vell.) …

by Ulysses Albuquerque

Bark regeneration and tannin content in Myracrodruon urundeuva Allemão after simulation of extractive damages—implications to management

by Ulysses Albuquerque

Tannin concentration in three simpatric medicinal plants from caatinga vegetation

by Ulysses Albuquerque

Analysis of rainfall and edge-effects on flavonoid levels in Bauhinia cheilantha (Bong.) Steud., Fabaceae

by Ulysses Albuquerque

Os efeitos da sazonalidade climática na caatinga sobre os teores de taninos em Myracrodruon urundeuva (Engl.) Fr. All. e Anadenanthera colubrina (Vell.) Brenan

by Ulysses Albuquerque

Análise da pluviosidade e do efeito de borda sobre os teores de flavonóides em Bauhinia cheilantha (Bong.) Steud., Fabaceae

by Ulysses Albuquerque

Predator cues and an herbicide affect activity and emigration in an agrobiont wolf spider.

by Samuel Evans

Kerri M. Wrinn, Samuel C. Evans, Ann L. Rypstra. 2012. Chemosphere 87:390-396.

Defenses of Caribbean sponges against predatory reef fish. I. Chemical deterrency

by Rob Toonen

Survey of anti-predatory defenses of marine sponges across the Caribbean

Gleadow RM, Haburjak J, Dunn JE , Conn M.E. and Conn EE (2008). Frequency and distribution of cyanogenic glycosides in Eucalyptus L’Hérit. Phytochemistry. 69, 1870-1874

by Ros Gleadow

Distinguishing Wild from Hatchery-Produced Juvenile Red Snapper with Otolith Chemical Signatures

by William Patterson

Abstract.—Otolith chemical signatures were evaluated as natural tags to distinguish wild from hatchery producedmore Abstract.—Otolith chemical signatures were evaluated as natural tags to distinguish wild from hatchery produced
juvenile red snapper Lutjanus campechanus. Otoliths were sampled from 59 hatchery-reared fish and 146 wild fish collected over the continental shelf from northwest Florida to Texas. One sagitta from each fish was cleaned, dissolved in ultrapure nitric acid, and analyzed with sector field inductively coupled plasma mass spectrometry to test for differences in otolith element:Ca ratios (Ba:Ca, Li:Ca, Mg:Ca, Mn:Ca, and
Sr:Ca) between wild and hatchery fish. The second sagitta was cleaned, ground to a fine powder, and analyzed with stable isotope ratio mass spectrometry to test for differences in delta (d) values of the stable isotopes 13C and 18O. Significant differences existed in otolith chemical signatures between hatchery and wild juveniles (multivariate analysis of variance, Pillai’s trace: P , 0.001). Jackknifed classification accuracies from linear discriminant function analysis indicated that hatchery fish could be distinguished from wild fish with 100%
accuracy based on otolith chemical signatures. The most important otolith chemistry feature in distinguishing hatchery from wild fish was d13C, with the mean difference in d13C between hatchery and wild fish (!2.6%) being similar to the mean difference in d13C between hatchery feeds and the predominant food of wild juveniles (!2.8%). Overall, results suggest that otolith chemical signatures may be employed as effective natural tags for mass marking of future stockings of red snapper or other marine fishes to estimate the hatchery contribution to wild populations.